"He’s a choke artist, I can’t believe," Trump said. "Are you sure he’s a Mormon? Are we sure?"

Trump has been at war with Romney since the former Massachusetts governor made a speech decrying the real estate mogul.

"He choked, he choked, it was so sad, he should have beaten Obama we wouldn’t be working, I could be back right now, I could be back working in New York and doing my deals and having fun and being with my family," he told the audience in Salt Lake City.

Ahead of the 2016 campaign, Romney spoke out about his faith and said that it would be part of his campaign if he ran, something he rarely mentioned in 2008 and 2012.

“For over ten years, as you know I served as a pastor for a congregation and for groups of congregations," he said.